Ring for fixing of sealing cover on ball joint

ABSTRACT

A straining ring for ball joint constituted of a sealing cover made of rubber with opening in the two ends, being one of bigger diameter to be coupled to the external part of the ball joint box, where it is provided the ring object of this invention, denominated sealing ring, and one of smaller diameter to be coupled to the body of the pin of ball end. The preferred sealing ring eliminates the machining that is required in the state of the art to fix this opening of bigger diameter of the sealing cover to the external face of the ball joint box and, due to its shape, involves a sealing lip made directly in the sealing cover, that may, optionally, have an internal knurling, and, being made of steel, has an internal flap that is mounted by interference on the external face of the ball joint box, which flap deforms itself when in the mounting process, in function of the existing interference, positioning itself in a specific angle and driving itself into the external face of the ball joint box in such a manner as to prevent the same from being removed, as, when one forces the sealing ring to outside the ball joint box, its internal flap is forced to the opposite direction, driving itself even further into the body. The sealing ring involves, further, the sealing lip provided in the sealing cover so that when carrying out the mounting process, the tool utilized for this purpose, presses the external flap of the sealing ring against the sealing lip and this against the external face of the ball joint box, providing a perfect sealing to the system and fastening the sealing cover in the interior of the sealing ring.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] This invention refers to a ring for fixing of a sealing cover onball joints that are applied in connections that require angular androtational movement of two pieces, more specifically, for application inautomotive vehicles.

[0003] 2. Description of Related Art

[0004] The ball joints intended for this purpose need a sealing systemto prevent impurities such as dust, sand and water from penetrating itsinterior and affecting the operation by the premature wearing out oftheir components, since these pieces operate by the coupling of theircomponents. The components must possess between themselves the bestpossible conformation, since, after the mounting of the coupled assemblyit is applied a certain load of displacement to the movable pieces,which load is produced by the friction of these movable pieces betweenthemselves. As a consequence, the presence of impurities between thepieces operating under friction action tends to cause a prematurewearing out of the components and the wear of the ball joint. The balljoints in the state of the art are normally composed of a pin with oneof its ends, the ball-type one, that is coupled to a bearing, of singleor split type. The ball joint assembly is mounted in the interior of abox, whose hole, through which has been mounted the ball pin and thebearing, is subsequently sealed by a boot or cover attached to the box,so as to prevent the entry of any impurity. At the end of the box,opposite to the closing cover, there is projected through an opening thenon-spherical part of the pin, called the body of the ball pin, to whichmust be fixed one of the pieces that requires angular and rotationalmovement, while the other piece is fixed to the box of the ball joint.In this way, the angular and rotational movement provided between theball pin and the casing of the ball joint must attend the needs of thepieces that are there connected. However, as well as is provided in thesealing of the box through the boot or cover placed therein, to preventthe entry of impurities in the interior of the ball joint, in theopposite end, through where is projected the body of the ball pin, thesealing system must be perfect and efficient, mainly due the fact thatit is in this place that the ball pin is moved angular and rotationallyrelative to the box. The state of the art protects this place with asealing cover that is constituted by a boot or cover made of elastomer,with the two ends open, one of bigger diameter, to be coupled to theexternal part of the box and the other of smaller diameter to be coupledto the body of the ball pin. When performing the coupling of theexternal part of the box, the fixing of the sealing cover normally iscarried out in a channel provided therein, where is placed the end ofbigger diameter of the sealing cover, the same being then overlappedwith an elastic ring commonly called straining ring, whose function isto fix the sealing cover on the box and prevent the entry of anyimpurity, being provided for the coupling of the body of the ball pin aring, commonly called sealing ring, whose function is to firmly fix thesealing cover on the body of the ball pin, preventing the entry ofimpurities, but not without allowing its rotational movement.

[0005] The fixing system of the sealing cover to the ball joint box,however, has shown some undesirable effects, related to the efficiencyof the sealing and to the high cost arising from the machining of thechannel in the box, to fasten the sealing cover, to the wasting ofmaterial resulting of the machining residues, and even to themanufacturing difficulties of the system related to the assembling ofthe straining rings on the ball joints, where may occur damages to theprotecting cover.

SUMMARY OF THE INVENTION

[0006] The present invention overcomes these undesirable effects,providing the system with a proper construction of the straining ringand with the shaping of the end of bigger diameter of the sealing cover,such new construction form of this straining ring providing a perfectconnection with the ball joint box. The structure of this inventioneliminates the machining of the box for the making of the channel, as itis required in the state of the art, and may be utilized directly in theforged or stamped box, without any machining whatsoever, never gettingloose from the assembling place in function of its form of constructionand, with the close cooperation of the very material of the sealingcover. The invention provides a perfect sealing of the system preventingthe entry of any impurity in the interior of the ball joint.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Next, this invention is detailed, being shown the description ofone preferred embodiment, as illustrated in the attached drawings, inwhich:

[0008]FIG. 1 shows the sealing cover coupled to the ball jointrepresented in longitudinal section; and

[0009]FIG. 2 shows the longitudinal cross-section, in enlarged detail,of the straining ring and sealing cover coupled to the ball joint.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0010] The figures show in the preferred embodiment of the invention,the sealing cover 1, for ball joint constituted by a pin with one of itsends, of spherical-shaped ball end 2, that is coupled to a bearing 3 andthe assembly mounted in the interior of a box 4. The sealing cover 1mounted on the non-spherical ball end of the pin of ball end 2 isprovided in the opening of smaller diameter with a sealing ring 5 thatfixes it to the body of the pin of ball end 2 providing the sealing ofthe system. The sealing cover 1 prevents entry of any impurity in theinterior of the ball joint, and also guarantees the desired rotationalmovement for the ball end pin 2. The sealing cover 1, at the end ofbigger diameter, has a sealing lip 6 and, involving this sealing lip 6there is provided the straining ring 7 made of steel, that is insertedwith interference in the box 4. In the mounting process, the internalflap 8 of the straining ring 7 that enters with interference in theexternal face of the box 4 of the ball joint, in function of theinterference, displaces itself against the sealing lip 6 of the sealingcover 1 driving itself in the box 4 in an angle that does not allow itsposterior removal, as, when forced to outside of the box 4. Thisinternal flap 8, for being driven in the box 4 of the ball joint in aspecific angle, tends to be forced in direction to the opposite side,being driven inside even further. On the other hand, in the mountingprocess, the tool utilized for such operation, when pressing thestraining ring 7 against the external face of the box 4 to overcome theinterference of the internal flap 8 of the straining ring 7, presses itsexternal flap 9, that involves the sealing lip 6, in such a way that thesame is pressed against the external face of the box 4 firmly adheringto it, including with the help of its internal knurled lip 10, what isoptional in the system, providing the required sealing. At the same timethis external flap 9 of the straining ring 7 closes itself against thesealing lip 6 fastening the sealing cover 1 in its interior.

[0011] From the foregoing description, it is clear that the presentinvention overcomes the undesirable effects of the prior art byproviding the system with a proper construction of the straining ringand with the shaping of the end of bigger diameter of the sealing cover.The new construction form of this straining ring provides an improvedconnection with the ball joint box. The structure of this inventioneliminates the machining of the box for the making of the channel, as itis required in the state of the art, and may be utilized directly in theforged or stamped box, without any machining whatsoever, never gettingloose from the assembling place in function of its form of constructionand, with the close cooperation of the very material of the sealingcover. The invention provides a perfect sealing of the system preventingthe entry of any impurity in the interior of the ball joint.

[0012] While the foregoing invention has been shown and described withreference to a preferred embodiment, it will be understood by those ofskill in the art that various changes in form and detail may be madetherein without departing from the spirit and scope of the presentinvention.

1. A ring for fixing of sealing cover in ball joint comprising: asealing cover made of elastomer with two ends open, one end of biggerdiameter to be coupled to an external part of a box and another end ofsmaller diameter to be coupled to a body of a ball end pin, wherein astraining ring, made of steel, is coupled to a sealing lip made directlyin the opening of bigger diameter of the sealing cover, that possesses aknurling in its internal face and, providing a machining of the externalface of the ball joint box mounted through interference of the internalface of the sealing ring with the external face of the ball joint box insuch a way as to define its internal flap.
 2. A ring for fixing ofsealing cover in ball joint, according to claim 1, wherein, whencarrying out the mounting, for a specific angle that drives the sealingring into the external face of the ball joint box to a point from whichit will not be possible to be removed, as, when one forces the ring tooutside of the ball joint box its internal flap tends to be forced inthe opposite direction, being driven into the body even further.
 3. Aring for fixing of sealing cover in ball joint, according to claim 1,further comprising an external flap that involves a sealing lip providedwith a knurling in the internal face of the sealing cover, in such a waythat when carrying out the assembly on the ball joint, the tool utilizedfor this purpose presses the external flap of the sealing ring againstthe sealing lip of the sealing cover and this against the external faceof the ball joint box, providing a sealing to the system and fasteningthe sealing cover in the interior of the sealing ring.